Inherit the RNA

A new study in Cell shows that C. elegans doesn’t need DNA or even epigenetics to pass traits down through the generations, says 80beats’ Veronique Greenwood. Some worms can use RNA to fight off viruses and that these molecules — and the ability to fight the virus — can be passed on for more than 100 generations, she adds. The researchers engineered worms that didn’t have the genes to make the RNAs necessary to fight a virus, and then bred them with worms that did have these genes for several generations. Some of the resulting offspring had ancestors with the virus-fighting molecules, but didn’t have the genes themselves. But when they observed the worms under the microscope, Greenwood says, the researchers saw that the gene-less worms were still fighting off the virus like their grandparents had. The researchers speculate that “the RNA molecules made by the original worms in response to a virus attack were floating around in the cytoplasm of the eggs and sperm that became their offspring,” Greenwood says.